Hi everyone,

Looking for some help please! My 1997 XK8 was sitting for 3 weeks in which time the battery died. Had it tested, confirmed dead so replaced it with new.

I've got power but no crank, all dash lights come on and go off as they should. Tried in neutral, park, with brake, without brake and with my foot on the brake really hard! Can unlock with the key and with the fob, red light by the gearstick goes off as normal. Can also hear a relay click below the gearstick when I put my foot in the brake when trying to crank.

I've checked all of the engine bay fuses on passenger side, the small cluster near the windscreen and the larger cluster about half way down the bay. I believe these cover the main potential culprits.
Also swapped the starter motor relay but still nothing.
Tried holding the battery leads together too.

So any ideas please? Having looked through the forums people mention tapping the starter motor and the car not recognizing the key so needs re-programming. Can't seem to find if these suggestions work in the old threads so anyone got any recent findings please?

Haven't tried tapping the starter as I have no idea where to find it!

Any help and suggestions appreciated.
Thanks Rich

 

Look up starter relays in engine bay, the set of relays in the black box in the shape of a T. Try the solution underneath this line first............

But I would bet good money on it being a bad battery connection particularly on the earthing side. Remove all the connectors. Sand them down. Re fix. Bet it starts first time.

Dont forget to let us know how you get on will you? One of my pet hates are those that come onto the forum. Post a help me please but we never hear from them again.

 

Thanks Frankc, I'll give that a go.
Will definitely post the progress, I feel your pain on that subject as I've not been able to find out if previous suggestions have worked.

 

+1 to frankc - check the car first for electrical gremlins.

The connections to your battery may look fine but it’s the ground connection to the body that may need cleaning up. Sand the surface shiney bright and use an electrical contact cleaner not WD40.

The positive cable goes to the HPP junction back behind the spare tyre. This connection can work loose. See pic below.



I had an intermittent start problem like yours and eventually changed my positive cable to a non-crimp solid copper modified cable. Cheap fix.

If that’s not the issue, then I would check the Earth strap on the engine. It’s on the RHS from the bell housing to right wheel well. See pic below.



Not easy to access this one so good luck and, as frankc said, let us know what you find.

 

Hi all,
Just an update I've tried the relays, cleaned the connections including to the HPP and ground all as above but still the same, power but no crank.

I'm thinking the chip inside the key isn't being recognised or the starter is knackered.
Where next or any other suggestions please?

 

You don't indicate where you live, but if it's a US model car the key will not have a chip.

 

Worth checking out this ongoing thread. Lots of good info, and my post #19 has an electrical schematic on all the modules involved in the start.

https://www.jaguarforums.com/forum/x...norway-226005/

You didn’t mention if you have checked the engine earth/ground?

 

Start with the easy stuff.
Can it be jump started? If so, your starter is good and your problems are at the battery, such as a connection.

 

Thanks for replies guys, it's a UK car, I haven't got to the engine ground as yet, its parked in an awkward place against the house which isnt helping!

Thanks for the link to the other thread too, I've had a scan through and looks like a few more things to try, particularly checking the security module.
It can't be jumped, just the same power but no crank.

I'll keep you updated and thanks again.

 

I had a problem with the crimp on the braided ground strap at the battery. The cable being very hot was a clue. Changed it to a solid cable and problem gone. All the lights came on as usual, but I guess there wasn't enough juice to get the starter cranking.

 

Just to close this off, the car ending up sitting dead for 18 months.
I had it towed to a local independent Jag guy and it was the immobilizer wasn't recognizing the key transponders so needed reprogramming.
Loads of other stuff required too having sat for so long but all up and running perfectly again now.

Thanks for your suggestions and hopefully someone might find this useful in the future.